1. Technical Field
The present invention relates to a liquid crystal display device and, more specifically, to a liquid crystal display device that includes both a transmissive portion for performing transmissive display and a reflective portion for performing reflective display in one subpixel and includes two electrodes for controlling alignment of liquid crystal molecules in one substrate.
2. Related Art
One example of a liquid crystal panel with a wide viewing angle is a liquid crystal panel of the fringe field switching (FFS) or in-plane switching (IPS) type. In these types, both a pixel electrode and a common electrode are provided in an element substrate, and liquid crystal molecules are rotated by control of an electric field occurring between both electrodes, thereby controlling alignment of the liquid crystal molecules.
Liquid crystal panels are broadly divided into the following types: a transmissive type which uses a backlight for displaying, a reflective type which uses reflection of outside light for displaying, and a transflective type which uses both transmissive and reflective structures built in one subpixel (see, for example, JP-A-2003-270627 and JP-A-2004-198922).
Existing transflective display devices of the twisted nematic (TN) type or electrically controlled birefringence (ECB) type suffer from an insufficient contrast and a narrow viewing angle. Transflective display devices of the vertical alignment (VA) type can have a high contrast and a wide viewing angle, but suffer from color changes in viewing from an angle.
In contrast to these TN or ECB display devices, transflective displays of the FFS or IPS type have excellent viewing-angle characteristics and have significantly small color changes in viewing from an angle, unlike VA transflective display devices. However, it is necessary to attach a retardation layer in order to perform both transmissive display and reflective display. This results in a problem of low contrast. In addition, the transflective FFS or IPS liquid crystal display device is thicker than transmissive FFS or IPS liquid crystal display devices.